Method and means of uniting copper to steel



all

Patented Apr. 20, i i

stares earner orr'ic.

ROBERT E. APPLEGATE AND JOHN B. AUSTIN, OF CLEVELAND, OHIO, ASSIGNORS TO RAIL WELDING AND BONDING COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF DELAWARE.

METHOD AND MEANS OE'UNlTING COPPER TO STEEL.

1T 0 Drawing.

Uniting Copper to Steel, of which the following is a specification. I

This invention relates to the art otarc Welding and is especially concerned with a method and means of uniting copper bonds to steel rails.

One-object of the invention is to provide a new and improved method of introducing degasilying substances continuously and in predetermined quantities into the molten metal forming the Weld metal in a' metallic joint.

filler rod or'electrode for use in the process of joining copper bonds to steel rails, having a suitable content of degasiitying substance.

more or less uniformly distributed therein. ;Another object is to provide a copper filler rod or electrode containing silicon for use in the process or uniting copper bonds to steel rails.

Other objects'will appear and be pointed out hereinafter.

Heretofore, so far as We are aware, diff ficulty has been experienced in uniting copper to copper or copper to steel in a manner to obtain a strong mechanical, good electrically conductive junction. A. primary cause-of such unsatisfactory joints is the presence of gases either combined or'oceluded, or both, in the molten copper which are liberated from combination with the molten metal as the metal cools but which remain entrapped therein thus causing V porosityf We have discovered that when stronger, more highly conductive junction.

these gases are suitably removed as suchfrom thefmolt'en' metal a dense, close grained, metallic structure is ohtained'which, by reason of\ its nonporous structure forms a -We have further discovered that highly satisfactory junctions may be obtained if the copper is treated with a. degaslfying substance thruoutt'he melting thereof and prefer to add the degasifying substance along with each increment of copper melted in the- Another object is to provide a'welding or lying substance. but there are many other Application filed March 13, 1922. Seria1 1 l'o. 5 3,486.

proportion and amount required for cone;

plete degasification of such increment.

Such addition of degasifying substance may be accomplished by incorporating inthe copper to be melted the substance in a substantially uniformly distributed condition,

which is easily possibleif such degasifying slightly more-degasi'fying substancein the added copper than is needed for its degasi-.

iication so that the molten portion of the copper article will be suitably degasified. In a similar manner pure copper melted into the joint-may beprovided for V] e prefer to employ silicon as a dgasimore or less suitable substances including aluminum, phosphorus, magnesium, boron and manganese, any one or more of which may be utillzed. lBor'the sake of brevity yre have used the terms copper and steel in this specification but We regard copper base alloys and iron, as full equivalents of the copper and steel mentioned above, and

accordingly intend the above terms to in-' clude these and other equivalent metals.

As a specific illustration of our improved 0 substances are employed as are readily solua steel or copper article We prefer to employ i method of uniting copper to steel, we have selected for description its application to the method-of attaching electrically conduetive copper bonds to steel railwaysrails, as

' practised heretofore and disclosed-in Letters Patent of the United States1,l83,992, and

ln practising our in 'ention We prefer to follow a part of the process outlined in said .patents, but touse copper filler wire containin redeternnn'ecl amounts of silicon tocomplete the bond head, instead of ordinary copper as used heretofore.

The silicon should be more orless uniformly distributed thruout the copper so gasification. When such amounts -or proportions of silicon tocopper are maintained after 0 that as the copper melts, veachmolten part carries with it sufilcient silicon for. its deabout 22% and 35% ling bond heads may such part is melted, the addition of degasifying substance beginning with the first molten metal, continuing as long as metal is melted and. always being present in substantially the required. amount for best results.

The silicon content may vary-over a relatively small range, preferably between by weight. A silicon content of about 25% has given good results. The degasifying substance need not, and preferably should not, be used in such amounts in the copper as toremain in considerable amounts in the .finished bond head. When the silicon content is about as stated above only about 0.12% will be found in the solidifiedmetal. i l/e have found that such amounts of silicon are adequate also to degasify portions of the bond head which are ordinarily melted in the process.

Gopper pontaining, silicon for use in makbeconveniently formed into rods-or wires, which form also lends itself readily to a variation of the silicon content in the molten metal by wrapping the rods with or around scrap copper.

Bonds attached to rails by this method have been found to be of close grained,-substantially nonporous structure and to be 'many times more firmly attached mechanically to the rail and to have a much higher electrical conductivity than bonds attached by the methods practisedheretofore. These notable improvements are due largely, we believe, to our improved method and means of removing substantially all gases as such ironrthe molt-en bond head metal before solidification thereof.

Although .we have described our invention in detail {as applied to the attaching of bonds to rails, we do not wish to be limited thereto since broadly our invention is applicable in the uniting of copper to copper or copper to steel where maximum strength and electrical conductivity are desired.

The scope of our invention is defined by what is claimed. What is claimed is l. The method of joining a copper bond to a steel rail which comprises forming a 'stantial amount and up to about ras er? suitable mold cavity about a portion of the copper of a bond to retain molten metal in contact with the rail and melting into the mold cavity copper having incorporated therein a substantial amount and up to about by weight of silicon to join the bond to the rail.

2. The method of joining a copper bond to a steel rail which comprises forming a suitable mold cavity about a portion of the copper of a bond to retain molten metal in contact with the rail, melting into the mold cavity a part of the bond and additional copper containing approximately 25% by weight of silicon substantially uniformly distributed therein to join the bond to the rail. j

3. The method of joining a copper bond to a steel rail which comprises forming asuitable mold cavity about a. portion of the copper of a bond to retain molten metal in contact with the'rail, melting into the mold cavity by means of an electric are a part of the bond and additional copper having incorporated therein a substantial amount and up to about .-5% by weight of silicon to complete the bond head and joining the bond to the rail.

I. As a new article of manufacture, a copper welding rod containing silicon in a substantial amount and up to about 35% substantially uniformly distributed therein.

5. As a new article of manufacture, copper for use in joining copper to steel containing silicon from about to 35%. a

6. As a new article of manufacture, copper wire for use in joining copper to steel containing about 25% of silicon by weight.

7. As a new article of manufacture, an alloy welding rod consisting predominantly of copper and haying silicon distributed substantially uniformly therein in a sub- 8. As a new article of manufacture, copper for use in joining copper to steel'containing silicon in a substantial amount and up to about 35%.

In testimony whereof, we hereunto aiiix our signatures, I

ROBERT P. APPLEGATE. JUHN B. AUSTIN. 

